All salivary assessments were performed in the absence of acute sialadenitis. All assessments were performed by the same observer. The flow rate was determined in every person according to the method described by Sreebny. Saliva was collected in a standardised manner. Patients were instructed not to eat, drink, or smoke for 90 minutes before the sialometric assessment. All assessments were performed at a fixed time of the day, between 10 am and 1 pm, in order to minimise fluctuations related to a circadian rhythm of salivary secretion and composition. The whole saliva sample was collected in pre-weighed plastic tubes using electronic scales.